Id`i*o*syn"cra*sy (?), n.; pl. Idiosyncrasies (#). [Gr. &?;; 'i`dios proper, peculiar + &?; a mixing together, fr. &?; to mix together; &?; with + &?; to mix: cf. F. idiosyncrasie. See Idiom, and Crasis.] A peculiarity of physical or mental constitution or temperament; a characteristic belonging to, and distinguishing, an individual; characteristic susceptibility; idiocrasy; eccentricity.

The individual mind . . . takes its tone from the idiosyncrasies of the body.

• a way of behaving or thinking that is characteristic of a person